The invention relates to protection of structures or other sites from blasts due to bombs or other explosive devices. The invention is particularly suitable for protecting buildings from car or truck bombs such as may be used in terrorist activities. The invention is equally applicable to any site requiring protection from ground level or low level explosive attack. In addition to blast protection, the invention is also applicable to protection from high velocity projectiles and debris associated with natural events such as hurricanes or tornadoes.
One common, worldwide method used by terrorist organizations is to use a bomb which is installed in a car, truck or other vehicle. The vehicle is driven adjacent to a target, and the bomb is then detonated in close proximity to the target. Examples of such attacks are the Oklahoma City federal building incident, the attack on the marine base in Beirut, multiple examples of IRA operations, and more recently a series of attacks on foreign interests in Saudi Arabia and the nightclub bombing in Bali. Clearly, vehicle bombing is employed for destructive ends by a wide variety of terrorist organizations all over the world.
However, existing means of blast protection are very difficult to use to protect most sites. Steel or concrete barriers must be extremely massive to be effective. For instance a concrete barrier adequate to protect against a 1500 lb truck bomb would have to be 7 feet thick or in the case of a solid steel wall, 14 inches thick. Clearly such barriers are not feasible to protect existing buildings in downtown city areas, where the streets may only be the width of a sidewalk from the building. Moreover extremely large barriers are very difficult and time consuming to fabricate and erect, making it impractical to provide blast protection from vehicle threats to existing buildings. Finally massive barriers are not aesthetic and architecturally harmonious with the vast majority of sites. Having to mar the appearance and functionality of sites to protect them from terrorism can be considered a victory for the terrorist in and of itself. Clearly, a more practical means of blast protection would be an important tool in the struggle against world-wide terrorism. The present invention provides a superior approach to site protection from blasts.